Patent EA-002208-B1 (EA)
Title: Production of detergent granulates
Inventor: AKKERMANS JOHANNES HEMDRIKUS M
IPC: C11D11/00
Filed: 1998-06-12
Abstract: 1. A process of forming a granular detergent product, the process comprising, in a gas fluidisation granulator, contacting a fluidised particulate solid material with a spray of liquid binder, such that the product of the particle density ((() and the excess velocity (Ue) of fluidisation gas relative to the mass flux of the spray (qmliq) when determined at the normalised nozzle-to-bed distance (Do) is set so that the flux number (FNm) as determined by   is at a critical value of at least 2 for at least 30% of the process. 2. A process of forming a granulator detergent product, the process comprising, in a gas fluidisation granulator, contacting a fluidised particulate solid material with a spray of liquid binder, such that the excess velocity (Ue) of fluidisation gas relative to the volume flux of the spray (qmliq) is set so Chat the flux number (FNv) as determined by   is at a critical value of at least 2 for at least 30% of the process. 3. A process according to claim l, wherein the mass flux of the spray (qmliq) is at least 0.1, more preferably at least 0.15, and is most preferably in the range 0.20-1.5 kgs<-1>m<-1>. 4. A process according to any preceding claim, wherein the the superficial air velocity (Us) is at least 0.45, more preferably at least 0.5, and is most preferably in the range 0.8-1.2 ms<-1>. 5. A process according to any preceding claim, wherein the process is a batch process and the critical value of FN is maintained for at least 30% of the contacting time. 6. A process according to any one of claims 1 to 4, wherein the process is a continuous process and the critical value FN is maintained at for least 30% of the contacting area. 7. A process according to any preceding claim, wherein the critical value of FN is maintained for at least 50% or 70%, preferably at least 75%, more preferably at least 80%, yet more preferably at least 85%, most preferably at least 90% and especially at least 95% of the process. 8. A process according to any preceding claim, wherein the critical value of PN is at least 2.3, more preferably at least 2.5 still more preferably, at least 2.6 and most preferably at least 3. 9. A process according to any preceding claim, wherein the critical value of PN is no more than 6, preferably no more than 5 and more preferably no more than 4.5. 10. A process according to any preceding claim, wherein the d3.2 average droplet diameter of the liquid binder is not greater than 10 times, preferably not greater than 5 times, more preferably not greater than 2 times and most preferbly not greater than d3.2 average particle diameter of that fraction of the total solid starting material which has a particle diameter of from 20 (m to 200 (m provided that if more than 90% by weight of the solid starting material has a d3.2 average particle diameter less than 20 (m then the d3.2 average particle diameter of the total solid starting material shall be taken to be 20 (m and if more than 90% by weight of the solid starting material has a d3.2 average particle diameter greater than 200 (m then the d3.2 average particle diameter of the total solid starting material shall be taken to be 200 (m. 11. A process according to any preceding, wherein minimum d3.2 average droplet diameter is 20 (m, preferably 30 (m, more preferably 40 (m. 12. A process according to any preceding claim, wherein the maximum d3.2 average droplet diameter is 200 (m, for example 150 (m, preferably 120 (m, more preferably 100 (m, most preferably 80 (m. 13. A process of forming a granular detergent product, the process comprising, in a gas fluidisation granulator, contacting a fluidised particulate solid material with a spray of liquid binder, such that for at least 30% of the process: (a) the excess gas velocity (Ue) is from 0.1 to 1.0 ms<-1> preferably from 0.3 to 0.9 ms<-1> more preferably from 0.4 to 0.6 ms<-1>; (b) the d3.2 average droplet diameter of the liquid binder is from 20 (m to 200 (m; and (c) the d3.2 average droplet diameter of the liquid binder is not greater than 10 times preferably not greater than 5 times, more preferably not greater than 2 times and most preferbly not greater than d3.2 average particle diameter of that fraction of the total solid starting material which has d3.2 a particle diameter of from 20 (m to 200 (m, provided that if more than 90% by weight of the solid starting material has a d3.2 average particle diameter less than 20 (m then the d3.2 average particle diameter of the total solid starting material shall be taken to be 20 (m and if more than 90% by weight of the solid starting material has a d3.2 average particle diameter greater than 200 (m then the d3.2 average particle diameter of the total solid starting material shall be taken to be 200 (m. 14. A process according to claim 13, wherein conditions (a), (b) and (c) are maintained for at least 50% or 70% of the process, preferably at least 80%, more preferably at least 85%, most preferable at least 90%, especially preferable at least 95% of the process. 15. A process according to any preceding claim, wherein the liquid binder comprises an acid precursor of an anionic surfactant and the particulate solids comprise an inorganic alkaline material. 16. A process according to any preceding claim, wherein a first portion of the liquid binder is admixed with a particulate solid starting material in a pre-mixer to form a partially granular solid material and then a second portion of the liquid binder is sprayed to contact the partially granular solid material in the gas fluidisation granulator to effect complete granulation. 17. A process according to claim 16, wherein the granular detergent product has a bulk density of from 350 to 650 g/1, wherein: (a) 5-75% by weight of total liquid binder is added in the pre-mixer; and b) the remaining 95-25% by weight of total liquid binder is added in the gas fluidisation granulator. 18. A process according to claim 16, wherein the granular detergent product has a bulk density of from 550 to 1300 g/1, wherein: (a) 75-95% by weight of total liquid binder is added in the pre-mixer; and (b) the remaining 25-5% by weight of total liquid binder is added in the gas fluidisation granulator.